Computer or data processing systems utilize various methods to increase the speed of data processing. One such technique is the utilization of a memory hierarchy design. For example, computer memory systems often include different levels of memory such as a fast cache memory structure along with a slower main memory. If a request for data is found in a cache memory structure (a cache “hit”), the time penalty associated with retrieving the requested data from main system memory is avoided. However, cache space is a valuable commodity. For example, the larger the cache memory size, the more real estate of the chip the cache requires as well as increased power demand.